So then attach a bucket to the string hanging from the spool, and add weights to it until the motor drops it.
The weight of the spool is of no importance, and if you use a rod, connect it to the rotor in the middle (so equally long parts of the rod sticks out in opposite directions), and its weight will not matter. Or you can attach it in the end, and add half its weight to the final bucket weight before calculating torque.
Also, torque is the product of force and distance. That is, oz*in, not oz/in. So when you have your weight, you multiply that with the length of the rod (or radius of the spool) to get the torque.
Arvid |